The goal of this proposal is to develop a nanometer-scale resolution computerized tomographic imaging system for small animal and molecular imaging. This will be achieved by developing a specialized x-ray source designed to work with x-ray compound refractive lenses. The source will provide intense, spatially uniform x-ray output over a large area with proper angular and spectral filtering. An x-ray detector must also be specially adapted for high-resolution imaging. Experiments during the first phase of the proposed work will confirm the expected utility of the complete system to be built. The end-product of the proposed research will be a table-top computerized tomographic imaging system for use in research laboratories using small animal disease models. This technology will have possibly the finest resolution of any in-vivo imaging modality and the ability to image large volumes of tissue and even entire organisms at ultra-fine resolutions, which will generate exciting images of development and disease not possible by current methods. This system can be used for both in-vivo imaging of small animals and ex-vivo imaging of microscopic biological samples. Given that the proposed technology is x-ray-based, the most immediate impact this technology will be in the morphological evaluation of radiodense tissues, such as calcified and ossified material. Additionally, this technology can potentially be used to interrogate compartments which contain exogenously administered radiodense contrast media, or for microscopic non-invasive imaging such as genetic phenotyping in insects such as Drosophila melanogaster. It should advance research into a wide range of disease entities that present a significant burden to society, including cancer, heart disease, osteoporosis and a wide range of bone disorders. The novel device will help bridge the chasm between the microscopic and clinical world, telling a highly detailed, intriguing story of growth, disease and therapy in a variety of developmental and preclinical models.